35 20 23.10.pdf

ALLEGHENY RIVER L/D 5, DAM SCOUR REPAIR

SECTION TABLE OF CONTENTS

DIVISION 35 - WATERWAY AND MARINE CONSTRUCTION

SECTION 35 20 23.10

DREDGING

PART 1 GENERAL

1.1 GENERAL REQUIREMENTS

1.1.1 Interference with Navigation

1.1.2 Placement of Dredged Material

1.2 SUBMITTALS

1.3 MATERIAL TO BE REMOVED

1.3.1 Above-Depth Rock

1.4 OVERDEPTH DREDGING

1.5 SOUNDINGS OR SWEEPINGS

1.6 ENVIRONMENTAL PROTECTION REQUIREMENTS

PART 2 PRODUCTS (Not Used)

PART 3 EXECUTION

3.1 INSPECTION

3.2 DREDGING

3.2.1 Safety of Structures

3.2.2 Plant Removal

3.2.3 Ranges, Gages, and Lines

3.2.4 Plant

3.3 DISPOSAL

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SECTION 35 20 23.10 Page 1 W911WN-09-B-0012 Revised by Amendment 0001

SECTION 35 20 23.10

DREDGING

PART 1 GENERAL

1.1 GENERAL REQUIREMENTS

Dredging shall consist of satisfactorily removing all riverbed materials necessary for the construction of stone scour protection. All dredged material shall be side cast to the location shown on the Contract Drawings.

1.1.1 Interference with Navigation

The Contractor shall coordinate the work effort with the lockmaster at this facility to assure that traffic is not interrupted.

1.1.2 Placement of Dredged Material

Dredged material shall be placed temporarily in a location as directed by the contracting officerdownstream or adjacent to the scour protection work. After placement of the filter fabric (see section 31 35 19.11 STONE SCOUR PROTECTION, paragraph PLACEMENT OF GEOTEXTILE), dredged material shall be placed on top of the filter fabric. Excess dredged material may remain in the location directed by the contracting officer if, dredged material is distributed in a uniform manner to minimize turbidity and approved byshall be uniformly distributed in place and coordinated with the Contracting Officer.

1.2 SUBMITTALS

Government approval is required for submittals with a "G" designation;

submittals not having a "G" designation are for Contractor Quality Control approval. The following shall be submitted in accordance with Section

01 33 00 SUBMITTAL PROCEDURES:

SD-06 Test Reports

Soundings or Sweepings; G, RE

Submit drawings of surveys during progress of work by soundings or sweepings.

1.3 MATERIAL TO BE REMOVED

The material to be removed to accomplish the work required in this section is anticipated to be silt combined with sand, gravel. The material may contain concrete rubble, logs and timbers, and other non-floating debris.

The Contractor is expected to examine the site of the work and make a determination of the character of the material for himself. Local minor variations in the subsurface materials are to be expected, and, if encountered, will not be considered materially different.

1.3.1 Above-Depth Rock

Large boulders and derrick stone protruding above the specified final river bottom elevation may be left in place on approval by the Contracting

SECTION 35 20 23.10 Page 2

Officer. The Contracting Officer shall be notified immediately as to the location and extent of this existing condition

1.4 OVERDEPTH DREDGING

To cover unavoidable inaccuracies of dredging processes, material actually removed to a depth of 1 foot below the depth specified and within the dredging limits as shown on the Contract Drawings will be measured and paid for at full contract price.

1.5 SOUNDINGS OR SWEEPINGS

Submit drawings of surveys during progress of work by soundings or sweepings.

1.6 ENVIRONMENTAL PROTECTION REQUIREMENTS

Provide and maintain during the life of the contract, environmental protective measures. Also, provide environmental protective measures required to correct conditions, such as oil spills or debris, that occur during the dredging operations. Comply with Federal, State, and local regulations pertaining to water, air, and noise pollution.

PART 2 PRODUCTS (Not Used)

PART 3 EXECUTION

3.1 INSPECTION

Inspect the work, keep records of work performed, and ensure that gages, targets, ranges, and other markers are in place and usable for the intended purpose. At the request of the Contracting Officer, furnish boats, boatmen, laborers, and materials necessary for inspecting, supervising, and surveying the work.

3.2 DREDGING

3.2.1 Safety of Structures

The prosecution of work shall ensure the stability of piers, bulkheads, and other structures lying on or adjacent to the site of the work, insofar as structures may be jeopardized by dredging operations. Repair damage resulting from dredging operations, insofar as such damage may be caused by variation in locations or depth of dredging, or both, from that indicated or permitted under the contract.

3.2.2 Plant Removal

Upon completion of the work, promptly remove plant, including ranges, buoys, piles, and other markers or obstructions.

3.2.3 Ranges, Gages, and Lines

Furnish, set, and maintain ranges, buoys, and markers needed to define the work and to facilitate inspection. Establish and maintain gages in locations observable from each part of the work so that the depth may be determined. Suspend dredging when the gages or ranges cannot be seen or followed. The Contracting Officer will furnish, upon request by the Contractor, survey lines, points, and elevations necessary for the setting

SECTION 35 20 23.10 Page 3 of ranges, gages, and buoys.

3.2.4 Plant

Maintain the floating plant and associated equipment to meet the requirements of the work.

3.3 DISPOSAL

Do not bring dredged material to the surface, except salvaged material as defined in paragraph "Salvaged Material" herein. Instead, side cast the material. Locations and procedures of temporary and final placement are to be submitted to the Contracting Officer. Large boulders and derrick stone encountered during excavation for downstream scour protection may be left in place with the approval of the Contracting Officer.

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SECTION 35 20 23.10 Page 4

3.3 DISPOSAL